[This corrects the article DOI: 10.3389/fvets.2026.1808217.].

Pasteurella multocida is an important bacterial respiratory pathogen of buffaloes and may cause major economic losses in the livestock sector. But there is a lack of data on its prevalence, risk factors, and antimicrobial resistance patterns in Bangladesh. The study was cross-sectional, and a total of 400 buffaloes from seven locations in Bangladesh were included in the nasal swab collection. Isolation was done using culture methods and confirmed by polymerase chain reaction (PCR). Associations between infection and risk factors were explored using logistic regression analysis; antibiotic susceptibility was determined by the disc diffusion method. The co-resistance patterns were assessed by Pearson's correlation analysis. The culture-based prevalence of P. multocida was 12.25%, compared with a PCR-confirmed prevalence of 7.25%; all PCR-positive isolates were capsular type B, with notable regional variation in prevalence. Buffaloes with respiratory symptoms had significantly greater odds of being infected (OR = 8.88, p < 0.001), and the younger group of animals aged 1-3 years had a greater predisposition to infection than the younger ones, but sex was not significantly associated with infection. The isolates exhibited high antibiotic resistance, as demonstrated by antimicrobial susceptibility testing, particularly against ampicillin (96.55%), oxytetracycline (93.10%), and penicillin-G (89.65%). Cefixime (93.10%) and azithromycin (68.96%) remained largely effective by contrast. Positive correlations were identified between resistance to β-lactams, tetracyclines, and aminoglycosides. These findings suggest that multidrug-resistant P. multocida type B is circulating in buffaloes in Bangladesh and highlight the need for increased surveillance, rational use of antimicrobials, and integrated control strategies.

Magnetic nanoparticles (NPs) are maintained in the body for a significantly longer duration than small molecule antibiotics, potentially facilitating prolonged therapeutic effects. In this study, a novel nanoantibiotic formulation (l-glu-Fe3O4-Amp NPs) was prepared, and its antibacterial efficacy was evaluated. For this purpose, l-glutamic acid (l-glu) was used for surface modification of iron oxide nanoparticles (Fe3O4 NPs), and ampicillin (Amp) was then conjugated l-glu-Fe3O4 NPs structure. Fourier transform infrared analyses revealed that the final nanoantibiotic formulation l-glu-Fe3O4-Amp NPs was successfully prepared. The size distribution of the formulation was determined to be 164 nm by ZETAsizer. It exhibited a controlled drug release profile over a certain period of time, with a slightly increased release and then exhibited a stable profile. Agar well diffusion assay and the LIVE/DEAD BacLight fluorescent assay showed that the formulation had an antibacterial effectiveness against both Bacillus cereus and Staphylococcus aureus. The formulation has a lower minimal inhibitory concentration value against S. aureus. It significantly increased the accumulation of reactive oxygen species in both bacteria when compared with the Amp group. Its cellular uptake and bacterial interaction were confirmed by confocal and transmission electron microscopy images. The in vitro assay revealed that this formulation is nontoxic to fibroblast cells. This study highlights the potential of l-glu-Fe3O4-Amp NPs conjugate as a potentially effective antibacterial agent. This is the first report on the use of l-glu as a surface modifier of Fe3O4 NPs and Amp. Use of l-glu increases the drug-carrying capacity of NPs and reduces the possible side effects of Amp.

Background/Objectives: Despite its hostile physicochemical environment characterized by high osmotic pressure, acidic pH, and low water activity, honey serves as a unique ecological niche for resilient microorganisms. This study aimed to recover bacterial isolates from honeys of different botanical origins and to characterize the probiotic-associated properties of a honey-derived Bacillus licheniformis isolate. Methods: A total of 20 bacterial isolates were recovered from four honey samples, including two blossoms and two honeydew honeys. 16S rRNA gene sequence analysis showed that the recovered isolates had taxonomic assignments consistent with Bacillus licheniformis. Because 16S rRNA sequencing does not provide sufficient resolution to establish strain-level diversity or clonality, one isolate, designated Blhoney, was selected for subsequent molecular and functional characterization. Results: In vitro assays revealed that Blhoney exhibits robust tolerance to simulated gastrointestinal stress, including extreme acidity (pH 1-3), bile salts (0.3-1%), pepsin, and pancreatin, maintaining viability for up to 24 h. Phenotypic antimicrobial testing demonstrated measurable inhibition zones for erythromycin, kanamycin, chloramphenicol, ampicillin, tetracycline, gentamicin, streptomycin, and spectinomycin, whereas no measurable inhibition zones were observed for penicillin G, rifampicin, ciprofloxacin, or ceftazidime. However, MIC determination and standardized breakpoint interpretation were not performed; therefore, these findings were interpreted solely as preliminary phenotypic inhibition-zone observations. Although the isolate did not display direct antagonistic activity against the tested bacterial pathogens under experimental conditions, its persistence under the tested gastrointestinal stress conditions supports further investigation of its probiotic-associated characteristics. Conclusions: Overall, these findings indicate that the honey-derived Blhoney isolate exhibits preliminary probiotic-associated characteristics under the tested in vitro conditions. However, further strain-level genomic and safety characterization is required before its potential probiotic application can be established.

Invasive pneumococcal disease complicated by infected aortic aneurysm is exceedingly rare and frequently fatal. We report the case of a 60-year-old man who presented with a 5-month history of fever and back pain. Imaging revealed a ruptured infected thoracoabdominal aortic aneurysm with L1 and L2 vertebral destruction. Both blood and tissue cultures yielded Streptococcus pneumoniae sensitive to penicillin G. Emergency in situ thoracoabdominal aortic replacement using a rifampicin-soaked four-branched prosthetic graft under cardiopulmonary bypass was performed successfully. Although cardiopulmonary bypass carries additional risks in a septic state, its use was considered unavoidable given the extent of aortic involvement and the need for selective visceral perfusion. Postoperative orthopedic consultation was obtained for management of vertebral osteomyelitis, including corset fabrication and supervised rehabilitation. Prolonged intravenous penicillin G for 6 weeks achieved microbiological eradication. At 3 months postoperatively, the patient remains under follow-up with no evidence of graft reinfection. This case underscores the importance of early cross-sectional imaging in patients with persistent fever and back pain, the diagnostic value of culture-positive confirmation, and the role of preventable risk factors including smoking and lack of pneumococcal vaccination.